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Old 03-27-2018, 10:07 PM
TimberArt TimberArt is offline
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Default 1/2" Acrylic

I have an advertising shop that wants me to cut 1/2" acrylic for a podium. They sent me the files which will consist of a total of 5 profile cuts. I have never cut this material before and would like to know what type of end mill to use and feeds and speeds as well.
Any help is greatly appreciated?
Bill
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Old 03-27-2018, 11:05 PM
Xray Xray is offline
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There might be optimal endmills for acrylic, I use whatever
i have handy so long as its good and sharp.
.125 passes, low RPM's to minimize melting issues and low feed to minimize stress on the bit.
With a sharp bit should get a decent finish but still will need some attention, I sand cut edges down with 120 grit sandpaper [using an orbital and mouse sander], then buff it to a polish as good as original.
If you don't have the luxury of a good bench buffer then you can look into flame polishing, or just leave it unbuffed for a frosted look

Should cut like butter with a good bit, I routinely cut out chunks as thick as 1.25 and rarely have any issues.
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Last edited by Xray; 03-27-2018 at 11:08 PM.
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Old 03-28-2018, 07:13 AM
TimberArt TimberArt is offline
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Thank you Xray, when you say low rpm exactly how low do you mean? I'm looking for numbers such as 100 ipm and 12000rpm etc. He is sending a 4x8 sheet and I wont have room left on it for testing.

Thank you,
Bill
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Old 03-28-2018, 11:15 AM
Jim_in_PA Jim_in_PA is offline
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There are cutters that are optimal for cutting plastics like acrylic for both the cut and the edge finish. That provides minimal additional processing after cutting. All the major cutter manufacturers have these. Talk with your cutter supplier in addition to what folks offer here.
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Old 03-28-2018, 02:52 PM
Xray Xray is offline
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I go by pitch so I couldn't say exactly, going literally at the lowest RPM wouldn't hurt.
I do that then jack it up slightly.

A full sheet wow, what hold down method you using ?
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Old 03-28-2018, 03:10 PM
jbiddle jbiddle is offline
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Last time I cut 1/2" polycarbonate, I used a Onsrud #63-725 1/4" O-flute running at 10,000 rpm, XY at 100 and Z at 30 ipm. Not sure how much different Poloycarbonate would be from Acrylic.
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Old 03-29-2018, 10:11 AM
BradyWatson BradyWatson is offline
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Quote:
Originally Posted by jbiddle View Post
Not sure how much different Polycarbonate would be from Acrylic.
WAY different animal. Get educated---> Onsrud Material Database

In fact, even acrylic will cut very differently from one color or manufacturer to another. Just 'acrylic' or 'polycarbonate' isn't enough information to make the best decision. Darker colors have more carbon in them & tend to be more rubbery than clear or lighter colors. This means that the shearing action of the tool needs to be different or the feeds altered to get a clean cut.

-B
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Old 03-29-2018, 10:23 AM
Ger21 Ger21 is offline
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There's also cast vs extruded, which also cut very differently.
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Old 03-29-2018, 05:41 PM
jbiddle jbiddle is offline
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Quote:
Originally Posted by BradyWatson View Post
WAY different animal. Get educated---> Onsrud Material Database

In fact, even acrylic will cut very differently from one color or manufacturer to another. Just 'acrylic' or 'polycarbonate' isn't enough information to make the best decision. Darker colors have more carbon in them & tend to be more rubbery than clear or lighter colors. This means that the shearing action of the tool needs to be different or the feeds altered to get a clean cut.

-B
Brady, great information! Thanks for the link.
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  #10  
Old 03-30-2018, 06:57 AM
TimberArt TimberArt is offline
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Quote:
Originally Posted by Xray View Post
I go by pitch so I couldn't say exactly, going literally at the lowest RPM wouldn't hurt.
I do that then jack it up slightly.

A full sheet wow, what hold down method you using ?
Going to use carpet tape under the pieces. I will have a bit of room to screw down the sheet.
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